Safety electrical device



Deb, 1 6, 1930. WADSWORTH 1,785,290

SAFETY ELECTRICAL DEVICE Filed June 4, 1929 2 Sheets-Sheet 1 BY @ZZM v aim A TTORNEYQ Dec. 16, 1930. 6. EL WADSWORTH SAFETY ELECTRICAL DEVICE Filed June 4, 1929 2 Sheets-Shoot 2 I/IIIIIIIIII/IIII'II/II! INVENTOR. gem e g w d 02% p [we ATTORN 5 III! N Patented Dec. 16, 1930 UNITED STATES PATENT OFFICE GEORGE E. WADSVIORTI-I, OF ERLANGER xENTUcKY, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO THE GEORGE B. WADSWORTH COMPANY, OF CINCINNATI, OHIO, A COR- PORATION OF OHIO SAFETY ELECTRICAL DEVICE Application filed June 4, 1929. Serial No. 368,244.

My invention is directed to the production of a fused switch mechanism in a, self-contained device comprising a switch, a fuse receptacle and means for preventing access to the fuse receptacle excepting when the switch is open together with means for preventing the closing of the switch so long as access to the fuse receptacle is permitted.

A broad object of the prese'nt'invention is 19 to simplify the construction of such devices and to make them more economical. Ancillary objects are the reduction of the numher and complexity of moldedinsulation parts, and the provision of means whereby metallic members be used with complete safety in constructing many of the parts of my device.

These and other objects of my invention, which will be pointed out hereinafter or will be apparent to one skilled in the art upon reading this specification, I accomplish by that certain construction and arrangement of parts of which I shall describe a preferred embodiment, reference being made to the drawings.

In the drawings:

Figures 1 and 2 are plan views of my device with the switch respectively in closed and open position.

Figure 3 is an elevation corresponding to the plan of Figure 1 and showing both the switch and the fuse receptacle closed.

Figure 4 is an elevation corresponding to Figure 2 showing the switch and the fuse receptacle open.

Figure. 5 is a section through the fuse receptacle and connected parts.

Figure 6 is a plan view thereof from beneath. I

Figure 7 shows in vertical section and plan the cover of the fuse receptacle.

Figure 8 shows in plan and elevation the operating member of my device.

Figure 9 is an elevation of the housing of the fuse receptacle column.

My device comprises a base 1 of insulating material provided with holes .2 whereby it may be mounted on a panel or in a box by means of screws or bolts. Substantially centrally of this base I provide an upstanding column 3 also of insulating material, Which column is hollowed out at the top as at 4: and contains a fuse receptacle. In the embodiment shown, the fuse receptacle is of the screw type and has a screw shell 5 of metal to which contact is made by a rod 6 and a collar 7 as will readily be understood. The rod 6 passes through a hole in the column 3, and at the base of the column passes through a metal strap 8 to which it is held by a nut 9. The strap is provided with the usual terminal screw 10.

Centrally of the column there is'a hole through which passes a second rod 11, bearing upon its upper end a threaded nut or .thimble 12 which acts as the central contact member of the screw receptacle for the fuse 13. The thimble bears against an insulating Washer 14 which overliesthe collar 7 and assists in holding the several parts in assembly. The bottom of the column 3 is cut away as at 15. 16 is the blade of a rotary knife switch mounted upon the rod 11 and held thereon by means of a nut 17. A washer 18 may be located upon the rod above the blade and a spring washer 19 located below it. These parts are most clearly shown in Figure 5. The blade 16 is adapted to rotate around the post 11 as far as may be permitted by the cut-out 15. There is located upon the base 1 a strap or metallic piece 20 bearing a contact screw 21 and a spring contact 22 adapted to receive the end of the switch blade 16.

The parts just described complete the electrical mechanism of my device. The terminal screw 21 is connected to the line side of a circuit and the terminal screw 10 is connected to the load side. When the switch is closed current may flow from the terminal screw 21 through the strap 20, the switch contact 22, the switch blade 16, the post 11, the fuse 13, the screw shell 5, the rod 6, the strap 8, and the terminal screw 10. In thearranga ment of the device shown in Figures 1 and 2, it will be clear how a movement ofthe switch knife in a counter clockwise'direction will open the circuit. When this is done, the fuse receptacle will not be connected with the line, and fuses may be changed with complete safety.

The remaining mechanism in my device provides means for operating the switch, together with means for preventing access to the fuse receptacle, the inter-relation of the said means being such that when the switch is closed, the fuse receptacle is covered and cannot be got at. It may be Opened when the switch is open and the circuit broken; but so long as it is open the switch may not again be closed. p

I provide a housing for the insulating column 3 consisting of a tube 23, the lower part of which has been cut out as at 24 so as to leave two legs 25, continuations of the tube, the lower ends of which are turned over to form attaching feet 26. The tube 23 is adapted to slip over the column '3, and-the feet 26 are bolted to the base by means of bolts 27 set in counter sunk holes. The tube 23 may fit tightly over the outside of the column 3 or may be fastened to it in any way desired. Or the column may be separately fastened to the base. Through the cut away portion 24 upon one side will extend the strap 8, and upon the other side the switch blade 16.

A cover is next provided for the fuse receptacle. It is formed of a section of tube 27 of such size that it will fit comparatively snugly over the outside of the tube 23 but not so tightly that it may not be easily moved with reference thereto. The top of this tubular-section is closed by a blade 28. The central portion of the tube is cut away on both sides as at 29 in Figure 7 so as to leave two leg-like portions 30 coiinecting an upper and lower cylindrical portion 31 and 32. The depth of the upper cylindrical portion 31 is such as to form a cover to house the fuse 13, and extend down over it at least to the topof the column 3.

Inone of the legs 30 there is machined a slot 33. The cover tube 27 is placed concentr'ically over the housing tube 23 and a pin 34 is screwed into the housing 23 and rides in the slot 33, so that the cover tube 27 may be "slid up and down on the housing tube 23 but may not be rotated with respect thereto. The pin 34, if made long enough, may extend somewhat into the column-3 so as to fasten the column into the tube; but it will not extend outwardly beyond the surface of 23 further than the thickness of the tube 27, because a rotary tubular part presently to be described is lo'cated outside the tube 27 and'conc'entrically with it. The housing tube 23 terminates at the top of the column 3; and the prop ortionin-g of the several parts is such th'at when the cover tube 27 is depressed as far as possible, it comp] etely covers and prevents access to the fuse 13'; but when it is elevated as far as possible, the cut-outs 29 in its sides will permit access to the fuse, and its removal or replacement, Next I provide a rotary op erating part comprising a tube 35 adapted to fit closely but not tightly over the cover tube 27. This tube has upper turned out cars 36 fern ed as will be clear from the drawings. These ears serve as grips whereby the tube may be rotated; but they may be varied as desired or in their place may be substituted operating handles of any suitable type. A piece of insulating material 37 is riveted as at 38 to the operating tube 35, and bears at its lower end a notch 39 adapted to engage over the switch blade 16, as is very clearly shown in Figures 3 and 4; and it will now be understood that a rotation of the tube 35 will open or close the switch, and further that the tube 35 is insulated from the electrical circuit. A slot 40 is cut in the tube 35 and a pin 41 passes through this slot and is fastened into the housing tube 23 as shown. The action of this pin and slot will be to permit the rotary movement of the operating tube but prevent its vertical movement or displacement with respect to the tube 23. The tubes 27 and 35, when in closed assembly, terminate at about the height of the cut-out 24 in the housing tube 23; and'since the pin 41 is located somewhat above this point, a notch 42 is cut into the lower part of the housing tube 27 to accommodate this pin. A second slot is cut into the operating tube 35 having a horizontal or radial part 43 and a vertical or longitudinal part 44. This may be referred to as a locking slot. A. pin extends through the slot and is fastened into the cover tube 27 but does not extend through it so as to engage the housing tube 23.

Reference now to Figures 3 and 4 will show that when the operating tube 35 has been rotated in a clockwise direction to the position shown, the switch is closed through the eugagenient of the blade 16 with the Contact The pin 45 lies in the horizontal part 43 of the groove, and the cover tube 27 cannot be raised. Thus the fuse is inaccessible. The tube 27 as explained cannot be rotated because it is pinned to the tube 23 by the'pin 34 extending through the slot 33. If however.

the operating tube 35 be rotated in a counter clockwise direction as to open the switch as in Figure 4, the pin 45 may be caused to enter the vertical slot section 44, whereupon the cover tube 27 may be pulled upwardly, the pin 45 riding in the slot 44 and the pin 34 riding in the slot 33. So long however, as the covertube-27 is in the upraised position, the operating tube 35 cannot again be rotated so as to close the switch, because the pin 34 holds the tube 27 from rotation with respect to the tube 23 and the pin 45 holds the tube from rotation with respect to the tube 27.

My device may be provided with a shield or cover to enclose the terminal screws 10 and 21 and the various live electrical parts. Ordinarily however, my device will be used in a bot: having a cover through a hole in which the upper parts of the operating and cover tubes extend. It will be understood that for ungrounded work two of my fused switch mechanism may be used together, one for each of the line terminals. When this is done, interconnecting means may be provided to permit the simultaneous operation of both and to inhibit the individual operation of either. Such means might be the connection of the two operating tubes 35 by a band, a chain, links or the like so that they must be rotated together.

Various modifications may be made in my device without departing from the spirit of it.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is

1. In an electrical device, a series of concentric tubes, one of said tubes comprising a housing, another a cover movable longitudinally with respect to said housing, and a third an operating tube movable in a rotary manner with respect to said housing, and means interrelating the movements of the said tubes whereby when the second of said tubes is in one longitudinal position, the third may not be rotated, and when the third has been rotated to a given position, the second may not be moved longitudinally.

2. In an electrical device, a series of concentric tubes, one of said tubes comprising a housing, another a cover movable longitudinally with respect to said housing, and athird an operating tube movable in a rotary manner with respect to said housing, and means interrelating the movements of the said tubes whereby when the second of said tubes is in one longitudinal position, the third may not be rotated, and when the third has been rotated to a given position, the second may not be moved longitudinally, the said means comprising pins riding in slots in the respective tubes.

3. In an electrical mechanism a central portion containing live electrical parts, a cover concentric with said central portion and movable longitudinally with respect thereto, said cover adapted in one position to prevent access to said live electrical parts and a rotary member concentric with said first two mentioned members and adapted in one position to inhibit the movement ofsaid second concentric part, said second concentric part adapted in one position to inhibit the movement of said third concentric part.

4. In an electrical device, a base and a column mounted on said base and containing a fuse receptacle, a concentric cover member surrounding said column and adapted to be 'IDOVQCl longitudinally with relation thereto,

said cover cut away in part to permit access to said fuse receptacle when in one position, a rotary member surrounding and concentric with said cover member, means on said rotary and cover members whereby selected positions of each will inhibit the movement of the other, a switch, and means on said rotary member to actuate said switch.

5. In an electrical device, a base and a central column of insulating material, said central column bearing a fuse receptacle and an operating part of a switch, a terminal member on said base connected with said fuse receptacle, a second terminal member on said base connected with the corresponding contact of the said switch, a cover member surrounding said column and adapted to expose said fuse receptacle by a longitudinal move ment, an operating member surrounding said cover member and adapted to operate said switch by a rotary movement.

6. In an electrical device, a base and a central column of insulating material, said central column bearing a fuse receptacle and an operating part of a switch, a terminal memher on said base connected with said fuse receptacle, a second terminal member on said base connected with the corresponding contact of the said switch, a housing member, a cover member surrounding said housing member and adapted to expose said fuse receptacle by a longitudinal movement, an operating member surrounding said cover member and adapted to operate said switch by a rotary movement, said members so interconnected that said cover member may not be moved to expose said fuse receptacle when said switch is closed, and said switch may not be closed while said cover member is in a position of exposing said fuse receptacle.

7. In an electrical device a base of insulating material, a column of insulating material holding a fuse receptacle, a terminal on said base connected with said fuse receptacle, a switch contact on said column also connected with said receptacle, :1 second switch contact on said base connected with a second terminal, a metallic tubular sheath surrounding said column, a metallic tubular cover sheath surrounding said first mentioned sheath, said. second sheath bearin a slot and the first mentioned sheath bearing a pin whereby said second sheath may slide longitudinally with relation to the first but may not be rotated, a third sheath surrounding said second, and bearing means for operating said switch, said third sheath bearing a transverse slot, a pin in said first sheath riding in said slot whereby said thirc sheath may be rotated with respect to said first but may not be moved longitudinally, an L shaped slot in said third sheath and a pin in said second sheath riding in said L shaped slot, whereby said third sheath may not be rotated with respect to said first when the pin on the second is in the longitudinal leg 'of the L shaped slot, and the second may not be moved longitudinally with reference to the first when the said pin is in the t ansverse section of the said slot.

8. In an electrical device a base of insulating material, a column of insulating material holding a fuse receptacle, a terminal on said base connected with said :tuse receptacle, a

switch contact on said column also connected with said receptacle, a second switch contact on said base connected with a second terminal, a metallic tubular sheath surrounding said column, a metallic tubular cover sheath surroundingsaid first mentioned sheath and W said second sheath bearing 'a slot and the first mentioned sheath hearing a pin whereby said second sheath may slide longitudinally with relation to the first but may not be rotated, a

third sheath surrou'nding said second, and

15 hearing means tor operatiir said switch, said third sheath bearing a trans erse slot, a pin in said first sheath riding in said slot whereby said third sheath may be rotated with respect to said first but may not be moved longitudi- QU nally, an i. shaped slot in said third sheath and a pin in said second sheath riding in said L shaped slot, whereby said. third sheath may not be rotated with respect to said first when the pin on the second is in the longitudinal leg of the L shaped slot, and the second may not he moved longitudinally with reference to the first when the said pin in the transverse section oi the said slot, said swtch coniprising a knife blade, and an insulating meni- 30 her attached to said third sheath and engaging said knife blade for the movement thereof.

GEORGE E. WADSVORTH. 

